Total Pageviews

Tuesday, December 29, 2009

TOKYO (AFP) – First came see-through frogs. Now Japanese researchers have succeeded in producing goldfish whose beating hearts can be seen through translucent scales and skin.The transparent creatures are part of efforts to reduce the need for dissections, which have become increasingly controversial, particularly in schools."You can see a live heart and other organs because the scales and skin have no pigments," said Yutaka Tamaru, an associate professor in the department of life science at Mie University."You don't have to cut it open. You can see a tiny brain above the goldfish's black eyes."The joint team of researchers at Mie University and Nagoya University in central Japan produced the "ryukin" goldfish by picking mutant hatchery goldfish with pale skin and breeding them together."Having a pale colour is a disadvantage for goldfish in an aquarium but it's good to see how organs sit in a body three-dimensionally," Tamaru told AFP.The fish are expected to live up to roughly 20 years and could grow as long as 25 centimetres (10 inches) and weigh more than two kilograms (five pounds), much bigger than other fish used in experiments, such as zebrafish and Japanese medaka, Tamaru said."As this goldfish grows bigger, you can watch its whole life," he said.Meanwhile another group of researchers who announced in 2007 they had developed see-through frogs said they planned to start selling the four-legged creatures, whose skin is transparent from the tadpole stage."We are making progress in their mass-production. They are likely to be put on the market next year," said Masayuki Sumida, professor at the Institute for Amphibian Biology of Hiroshima University.Sumida said see-through tadpoles and adult frogs would be available in the first half of next year in Japan for laboratories and schools and as pets, with a price tag expected to be below 10,000 yen (110 dollars) each.He also wants to sell the creature abroad.Animal rights activists have pressed for humane alternatives to dissections, such as using computer simulations.Sumida's team produced the creature from rare mutants of the Japanese brown frog, or Rena japonica, whose backs are usually ochre or brown. Two kinds of recessive genes have been known to cause the frog to be pale.While goldfish are easier to keep, frogs are higher forms of life and therefore preferable for experiments, Sumida said.

Monday, December 14, 2009

This is my first line of Zebrafish I named “Absolute.” It will be useful in many areas of research. It is a cross of rose^b140 which lacks guanine and nacre^b692 which lacks melanin.

I just started distributing them to the research community. Someone I sent them to in Japan mentioned their friend was working on a clear goldfish for similar areas of research. The clear goldfish have just been published:

“The clear goldfish have just been in the news papers. The Yomiuri Shimbun

With Christmas around the corner, a see-through goldfish might make a nice Christmas present for the ichthyologist who has everything.

The goldfish, with transparent scales that reveal its organs, was developed by a joint research team of Mie University and Nagoya University.

The fact that it grows to weigh as much as 1 kilogram will make it useful for research into blood constituents and organ behavior. A report announcing the development of the fish was made at the annual meeting of the Molecular Biology Society of Japan in Yokohama on Wednesday.

The research team bred the transparent fish by repeatedly crossing selected pale goldfish over three years.

As goldfish lay several thousand eggs at a time, they will make useful experimental subjects for the observation of blood makeup and the operation of internal organs without scientists having to dissect them.

In research carried out to hitherto, transparent zebrafish, which also lay a large number of eggs, have often been used, but they are ill-suited for research into studying blood and organs as they are small, weighing about 3 grams.